There currently is a need for integrated circuits with higher density and increased functionality. To meet this need, it is necessary to reduce the dimensions of the integrated circuit's transistors. For example, it is expected that future integrated circuit transistors will be fabricated with effective channel lengths of one hundred nanometers or less.
Such small transistors often suffer from fringing fields and other short channel effects which degrade performance and diminish control over the transistor's operation. To reduce the short channel effects, a thinner gate dielectric often is used. However, the thin gate dielectric often results in excessive gate leakage current, which increases power and lowers the performance of the integrated circuit.
Hence, there is a need for a transistor that has small physical dimensions but does not suffer from short channel effects or excessive gate leakage current.